RQ00828 - Software Developer - Full Stack - Senior

Maarut; Toronto; On-site; CAD 120,000 - 180,000; Full time

Job summary

Maarut is seeking a senior specialist to advance FHIR subscription workflows and HL7 v2 integrations within Ontario health standards. You will design, implement, and support Java/Node.js services, React components, and serverless processing with AWS Lambda.

You will work on SubscriptionTopic definitions, conformance testing, and enterprise Pub/Sub integrations, delivering reliable event processing and secure handling of patient data.

Qualifications

• Experience with FHIR Subscription/SubscriptionTopic workflows.
• Senior Java and Node.js development for REST APIs and FHIR integrations.
• Hands-on with AWS Lambda and asynchronous queues.
• React development with SMART on FHIR launch/auth
• HL7 v2 and Ontario digital health standards experience.

Responsibilities

• Map workflows to SubscriptionTopic and behavior for enterprise Pub/Sub.
• Define and maintain SubscriptionTopic resources and supported event definitions.
• Implement subscription lifecycle, delivery config, heartbeat and event retrieval.
• Develop Java/Node.js services publishing events and routing actions.
• Develop React components using SMART on FHIR to support workflows.
• Maintain Mirth channels and HL7 v2 integrations with FHIR resources.

Skills

FHIR Subscriptions

SubscriptionTopic

Java & Node.js services

REST APIs

AWS Lambda

React & SMART on FHIR

HL7 v2

NextGen Connect (Mirth)

Ontario health standards

Education

Bachelor's degree in Computer Science or related field

Tools

NextGen Connect (Mirth)

HL7 v2

AWS Lambda

FHIR APIs

Job description

Required Skills

• Strong hands-on experience with FHIR Subscription and SubscriptionTopic, including topic definitions, resource triggers, filter criteria, subscription status and lifecycle, notification Bundles, delivery channels, heartbeat notifications, and event retrieval.
• Senior-level experience developing Java and Node.js services, REST APIs, FHIR integrations, event publishers and consumers, and production application logic.
• Strong experience implementing FHIR Subscription and SubscriptionTopic workflows with AWS Lambda and asynchronous queues, including notification Bundle handling, retries, dead-letter handling, idempotency, concurrency, duplicate-event handling, and replay.
• Strong React development experience building production applications that use SMART on FHIR launch, authorization, context, scopes, and FHIR API integration patterns.
• Hands-on experience with NextGen Connect (Mirth), HL7 v2 integration, and Ontario digital health standards and provincial services, including the Hospital Report Manager (HRM) Standard, Provider Registry, Client Registry, and eReferral, covering message transformation, validation, routing, acknowledgements, error handling, conformance testing, and production support.

Responsibilities

• Assess polling-based integrations and workflows, identify the clinical or application events that should trigger notifications, and map each workflow to the appropriate FHIR SubscriptionTopic and Subscription behaviour.
• Define, implement, and maintain SubscriptionTopic resources, including supported resource triggers, event definitions, filter parameters, notification shapes, and conformance requirements.
• Implement Subscription creation, validation, activation, status management, renewal, deactivation, delivery configuration, heartbeat handling, event retrieval, and subscriber lifecycle controls.
• Design, develop, test, and support Java and Node.js services that publish events, manage subscriptions, consume notification Bundles, call FHIR APIs, and route resulting actions to application workflows.
• Develop and maintain AWS Lambda functions and queue-based integrations for asynchronous event processing, validation, enrichment, workflow coordination, and downstream application updates.
• Implement reliable processing controls for idempotency, duplicate detection, retries, dead-letter handling, controlled concurrency, ordering where required, reconciliation, replay, and recovery.
• Develop and support React applications that use SMART on FHIR to present subscription-related workflows, launch within supported contexts, obtain authorized FHIR access, and interact with FHIR resources and application APIs.
• Develop and maintain NextGen Connect (Mirth) channels that receive, transform, validate, route, and acknowledge HL7 v2 messages and connect those workflows to FHIR resources, application services, and Enterprise Pub/Sub events.
• Validate Subscription, SubscriptionTopic, notification Bundle, and related FHIR resource instances against the applicable FHIR definitions, The Agency profiles, terminology, and business rules.
• Implement event correlation, structured logging, metrics, alerts, audit records, subscription health monitoring, and operational dashboards so teams can trace processing across publishers, Enterprise Pub/Sub, subscribers, and downstream applications.
• Create and maintain unit, integration, contract, conformance, interface, regression, end-to-end, performance, and failure-recovery tests covering FHIR subscription workflows, backend services, serverless processing, HL7 v2, and React components.
• Apply secure configuration, authentication, authorization, least-privilege access, privacy-aware logging, and appropriate handling of personal health information, and prepare technical designs, mappings, runbooks, and knowledge-transfer materials with project stakeholders.

Desired Skills

• Experience implementing the FHIR R5 Subscription model or the R5 subscription backport for earlier FHIR releases, including SubscriptionTopic, rest-hook or websocket delivery, status notifications, heartbeat notifications, and event retrieval.
• Experience with AWS messaging, integration, and observability services such as Amazon SQS, Amazon SNS, Amazon EventBridge, Amazon API Gateway, and Amazon CloudWatch.
• Experience with infrastructure as code, automated build and deployment pipelines, containerized workloads, configuration management, and automated security scanning.
• Experience defining versioned FHIR profiles, event schemas, interface contracts, compatibility rules, correlation identifiers, and governance practices for shared enterprise integrations.
• Experience using NextGen Connect (Mirth) to integrate with Ontario digital health standards and provincial services, including the Hospital Report Manager (HRM) Standard, Provider Registry, Client Registry, and eReferral, with hands‑on responsibility for HL7 v2 transformation, validation, routing, acknowledgements, conformance testing, and production support.

Required Competencies

• Advanced FHIR Subscription and SubscriptionTopic experience, including resource triggers, filter criteria, lifecycle and status management, notification Bundles, delivery channels, heartbeat notifications, event retrieval, validation, and conformance testing.
• FHIR Subscription and SubscriptionTopic implementation experience for event-driven clinical workflows, including topic and event design, subscription filters and lifecycle management, notification Bundle processing, asynchronous queue processing, idempotency, retries, dead-letter handling, duplicate-event handling, observability, replay, and production troubleshooting using Java, Node.js, and AWS Lambda.
• React and SMART on FHIR experience, including launch and authorization flows, scopes, context handling, FHIR API integration, accessible user-interface development, automated testing, and secure handling of clinical information.
• NextGen Connect (Mirth), HL7 v2, and Ontario digital health standards experience, including the Hospital Report Manager (HRM) Standard, Provider Registry, Client Registry, and eReferral, covering message transformation, validation, routing, acknowledgements, error handling, interface and conformance testing, production support, and integration with FHIR, Java, Node.js, or serverless components.

Rated Criteria

• Advanced FHIR Subscription and SubscriptionTopic experience, including resource triggers, filters, lifecycle and status management, notification Bundles, delivery channels, heartbeat notifications, event retrieval, validation, and conformance testing. 25 Points
• Demonstrated FHIR Subscription and SubscriptionTopic implementation experience using Java, Node.js, AWS Lambda, and asynchronous queues, including topic and event design, subscription filters and lifecycle management, notification Bundle processing, idempotency, retries, dead-letter handling, duplicate-event handling, replay, observability, and production troubleshooting. 25 Points
• React and SMART on FHIR experience, including launch and authorization flows, scopes, context handling, FHIR API integration, accessible user-interface development, and testing. 25 Points
• NextGen Connect (Mirth) and HL7 v2 integration experience, including transformation, validation, routing, acknowledgements, error handling, interface testing, and integration with Ontario digital health standards and provincial services such as the Hospital Report Manager (HRM) Standard, Provider Registry, Client Registry, and eReferral. 25 Points

Requirements

Deliverables

• FHIR SubscriptionTopic definitions and supporting artifacts that document event triggers, supported filters, notification content, delivery expectations, and conformance rules for assigned Enterprise Pub/Sub workflows.
• Subscription lifecycle components for creation, validation, activation, status management, renewal, deactivation, delivery configuration, heartbeat handling, event retrieval, and subscriber support.
• Updated Agency applications and workflows that integrate with Enterprise Pub/Sub and replace assigned polling-based processes with FHIR subscription-driven event processing.
• Production-ready Java and Node.js services, APIs, publishers, consumers, adapters, and integration components for managing subscriptions and processing FHIR events and notifications.
• AWS Lambda functions and queue-based processing components for validation, enrichment, retries, dead-letter handling, idempotency, duplicate detection, reconciliation, replay, and downstream updates.
• React components that use SMART on FHIR launch, authorization, context, scopes, and FHIR APIs to support the assigned subscription and application workflows.
• NextGen Connect (Mirth) channels and configurations for HL7 v2 ingestion, transformation, validation, routing, acknowledgement handling, error management, and integration with FHIR and event-processing components.
• FHIR profiles, examples, validation rules, event and interface mappings, contract tests, conformance tests, integration tests, end-to-end tests, and release-validation evidence.
• Structured logs, metrics, alerts, dashboards, subscription health monitoring, audit records, reconciliation controls, incident diagnostics, operational procedures, and production-support runbooks.
• Technical designs, API and interface specifications, workflow documentation, security and configuration notes, deployment instructions, demonstrations, release-support materials, and knowledge-transfer artifacts.

Must Haves

• Advanced FHIR Subscription and SubscriptionTopic experience, including resource triggers, filters, lifecycle and status management, notification Bundles, delivery channels, heartbeat notifications, event retrieval, validation, and conformance testing. 25 Points
• Demonstrated FHIR Subscription and SubscriptionTopic implementation experience using Java, Node.js, AWS Lambda, and asynchronous queues, including topic and event design, subscription filters and lifecycle management, notification Bundle processing, idempotency, retries, dead-letter handling, duplicate-event handling, replay, observability, and production troubleshooting. 25 Points
• React and SMART on FHIR experience, including launch and authorization flows, scopes, context handling, FHIR API integration, accessible user-interface development, and testing. 25 Points
• NextGen Connect (Mirth) and HL7 v2 integration experience, including transformation, validation, routing, acknowledgements, error handling, interface testing, and integration with Ontario digital health standards and provincial services such as the Hospital Report Manager (HRM) Standard, Provider Registry, Client Registry, and eReferral. 25 Points